Has my implant run out?!

I’m due to have my implant taken out at the end of December, ive had it for 3 years and not had a single period in that time, however i now have a really painful heavy period ( probably not that bad but as i haven’t had one in so long it seems it). Do you think this means the implant may have stopped working early and is no longer working? is it safe to have sex when it stops or no? ￼